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Delaying a one-shot (monostable) pulse?

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dougie

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With a monostable 555 timer, what would be the easiest way to delay this pulse?

With an astable timer, I would use maybe a shift register or JK flip flops as frequency dividers, but I just can't figure it out for a one shot.
 
Wire it to a 2nd monostable...Make that 2nd monostable have a pulse duration of the desired delay value. Diffrentiate it's output and feed it to a 3rd monostable so as to trigger the 3rd monostable at the -ve edge. The pulse width of the 3rd monostavle is the same as that of the 1st monostable.

So you get a delay of the pulse specified by the 2nd monostable.

You may aswell chuck the 1st monostable and manage your show with the 2nd and the 3rd monostable. Use a 556 IC.

Have I made myself clear or do I sound like I am juggling with words?
 
Wouldn't it be easier just to use a cap, resistor, and comparator? Once the cap is charged to a voltage set to the by the potentiometer, you could start up the power to the 555. I have attached a psuedoschematic. It my not be fully correct, for my fluency of electronics is relatively low at the moment. Please forgive me :)
 

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lord loh. said:
Wire it to a 2nd monostable...Make that 2nd monostable have a pulse duration of the desired delay value. Diffrentiate it's output and feed it to a 3rd monostable so as to trigger the 3rd monostable at the -ve edge. The pulse width of the 3rd monostavle is the same as that of the 1st monostable.

So you get a delay of the pulse specified by the 2nd monostable.

You may aswell chuck the 1st monostable and manage your show with the 2nd and the 3rd monostable. Use a 556 IC.

Have I made myself clear or do I sound like I am juggling with words?

I'm a little bit new to electronics, could you define what you mean by the '-ve' edge? And could you also explain what you mean by 'diffrentiate it's output'?

Thanks
 
The term "-ve edge" or negative edge is shorthand referring to one part of the typical rectangular waveform (or 'square wave') at which the voltage is falling from a high value to a low value. Since this change is typically very fast in a digital circuit, it is referred to as an edge. You might also hear the other term "positive edge". The positive and negative edges are often also referred to as the rising and falling edges or even the leading and trailing edges.

To differentiate its output is a mathematical reference. If you have studied basic calculus, you will have heard of the term "to differentiate". It really means to calculate the instantaneous slope of a value which is assumed to be changing. I hope you know what slope means. You will learn as you go into electronics that mathematics is used to describe the behavior of electronic circuits because those circuits are extremely predictable using such mathematics. So learn as much math as you can manage. Its all useful in electronics. When he says to differentiate the signal, he refers to using a simple circuit which "takes the differential of" the signal. The most common circuit to do this is with a series connection of a capacitor followed by a shunt connection of a resistance. We often refer to such simple configurations as an RC circuit for obvious reasons. To explain further needs a schematic so, being lazy, I will stop here.
 
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